/Engine/Source/Runtime/Sockets/Public/SocketSubsystem.h
Bind to next available port.
The bound port number, or 0 on failure
int32 BindNextPort ( [FSocket](API\Runtime\Sockets\FSocket) * Socket, [FInternetAddr](API\Runtime\Sockets\FInternetAddr) & Addr, int32 PortCount, int32 PortIncrement )